Size: Adults are 1/4 inch to 3/8 inch long with compact, wide bodies.
Color: Blow flies are usually shiny and metallic ranging from bright blue to coppery orange to almost black.
Habits: Blow flies are extremely common. They are loud buzzing fliers that are attracted to lights, food odors and warm/cool currents around windows and doors. The sudden appearance of dozens of blow flies in a building could indicate there is a dead rodent, bird, or other animal in the wall, ceiling or attic.
Diet: Blow flies are scavengers that feed on trash, decaying animals and animal feces. They are usually the first insects to reach a dead animal. Blow flies are an important part of the decomposition process because they recycle nutrients back into the soil.
Reproduction: Female blow flies lay several hundred eggs on or near suitable food sources such as garbage containers, dumpsters and compost piles. Tiny maggots hatch from eggs in 6 to 48 hours then undergo several stages before becoming adult flies. It takes 16 to 35 days for the development from egg to adult.
Other Information: Maggots have hook-like mouth parts that tease apart tissues in which they live. Adults have sponge-like mouth parts similar to those of house flies. Blow flies are important decomposers of dead animals and other rotting organic material, such as decomposing plant material. Their larvae are frequently used in forensic science to determine facts about a crime scene.
Size: There are several species of carpenter bees that are fairly small, but the common species that may invade structural wood are some of the largest bees in North America, with some of the largest over one inch long.
Color: Carpenter bees are normally shiny metallic blue-green to black, although the male may be light tan.
Habits: Carpenter bees are solitary bees that get their name from their habit of boring chambers in solid wood in order to create living quarters for their larvae. The wood is not eaten, but instead is reduced to sawdust, called frass, and ejected from the tunnels. The female carpenter bee does the excavating, and several females may work in the same section of wood and use the same entrance hole, but they create separate galleries for housing their larvae. The galleries may be used repeatedly, with each new female lengthening the tunnel, which often can reach over ten feet in length.
Diet: Carpenter bees dine on pollen and nectar.
Reproduction: Males and females spend the winter in old galleries and emerge in the spring to mate. The female creates an average of six or seven cells; each separated by a plug, and places an egg and a food supply of pollen and nectar in each cell. Once this is completed she never returns to care for the larvae. The male carpenter bee guards the outside of the nest and attempts to chase away predators. The male does not have a stinger, but can cause concern with his hostile buzzing.
Other Information: Damage from carpenter bees is hidden within wood, often with only the round entrance hole visible. Males can be very aggressive, but do not have a stinger. Females do have a stinger and will sting if they become agitated. Carpenter bees often use the same tunnels and galleries year after year and wood damage can become extensive.
Size: Yellow jackets can grow to an inch long.
Color: Yellow jackets are yellow and black, and specific identification of each species is done with differences in the patterns of the black patches. Yellow jackets have two pair of wings that are of different shape and size.
Habits: Yellow jackets are social wasps that live together in colonies. A queen initiates the colony and female workers build the nest, care for the young, forage for food, and defend the colony. Colonies typically begin each spring and die off each fall, but may survive over the winter in warmer climates. The population of the colony easily grows to many thousands of workers. At the end of the summer, males are produced, mating takes place, and fertilized queens over-winter in protected locations. Nests are placed in aerial locations such as trees, shrubs, wall voids, or attics, as well as in the ground, where workers enlarge holes they find to accommodate the growing colony. Colonies near a home are dangerous and should be eliminated.
Diet: Adults feed on sweet liquids such as honeydew, nectar, fruit juices, or human foods such as soda.
Reproduction: Queens emerge during the spring and select a nest site. They then build a small paper nest in which to lay their eggs. After eggs hatch, the queen feeds the young for about 20 days. By mid-summer, the adult workers emerge and begin nest expansion, foraging for food, care of the queen and larvae, and colony defense.
Other Information: Yellow jackets are some of the most aggressive wasps and will sting repeatedly to defend their colony from perceived intruders. Many people think yellow jackets are bees, however, they are wasps.
Size: The adult house fly reaches 1/2 inch long.
Color: House flies are dark gray and easily distinguished by the pattern of wing veins, four dark longitudinal stripes on the top of the thorax, and the yellow sides of the abdomen on the males.
Habits: The house fly got its name from its common occurrence in homes, particularly during more rural times when horses and livestock were used as transportation. House flies are found just about anywhere there are humans and often swarm near garbage piles and manure. They are considered a health risk and should be eliminated whenever possible.
Diet: House flies eat a wide variety of food including human food, animal food, carcasses, garbage and excrement. They cannot eat solid food and have sponge like mouthparts that they use to suck up pre-digested, liquefied food.
Reproduction: The house fly breeds prolifically, with females laying anywhere from 350 to 900 eggs in their lifetime, with a record of 2,400 eggs from a single female fly. The interval from egg to adult fly can be completed in less than one week under warm, moist conditions, and there can be many generations each year. Adult flies live as long as 54 days and females mate multiple times. Breeding sites include any moist, decomposing organic material, such as lawn clippings, manure, animal waste, soiled garbage containers, outhouse receptacles, and decomposing plant materials.
Other Information: These flies are inactive at night and rest on ceilings, beams and overhead wires within buildings, trees, and shrubs, various kinds of outdoor wires, and grasses. House flies can transmit more than 100 different pathogens.